This invention relates to data storage disk drives in which heads read and write data on a storage disk and more particularly to an improved head cleaner which cleans the heads when they are moved out of engagement with the recording medium.
Contamination build up on the air bearing surface of recording heads is a common problem in removable disk drives. Cleanness maintenance of the recording head is thus an important part of drive development work. In the JAZ(copyright) drive supplied by Iomega Corporation, assignee of the present application, the heads are loaded at low RPM so that there is contact between the head slider and the disk surface. This is intended to keep debris off of the slider surface. However, as the linear recording density increases, the disk surface becomes much more smooth and this reduces the effectiveness of debris removal during low RPM head loading.
A load ramp assembly is used to clean the heads in the ZIP(copyright) drives supplied by Iomega Corporation.
U.S. Pat. No. 5,768,059, Bishop et al. shows a disk drive in which the position of the magnetic heads with respect to the disk is carefully controlled during the loading and unloading of the heads. Head loading and unloading is accomplished in an efficient displacement, thus assuring that the heads will not be destroyed during the load/unload process. By reducing the vertical displacement, more heads and more disks can act in the same vertical height, thereby allowing more data storage capacity in the same form factor or volume.
Wings on the heads control the vertical position of the head. The wings are in close proximity to the heads to fully ensure that the motion of the wing is the motion of the heads. The wings ride on opposed profiles as the actuator carriage moves toward and away from the disk. As the heads move toward the disk, first opposed profiles separate the heads so that the heads can pass on both sides of the disk. Further travel of the actuator causes the wings to ride over second opposed profiles which bring the heads together onto the disk in a controlled manner. As the heads are retracted from the disk they are parked and moved across a cleaning pad.
The ORB drives supplied by Castlewood have a load ramp assembly similar to the ZIP drives. U.S. Pat. No. 5,973,886, Kuhn is an example of a Castlewood drive. A brush like material was used in the ORB drive as a head cleaner.
Testing shows that this head cleaner is not very aggressive so that debris smeared on the air bearing surface of the slider is not removed by the head cleaner. The head cleaner is only effective in moving loose debris accumulated on the slider around.
It is an object of the present invention to provide an improved head cleaner for a disk drive.
In accordance with the present invention a head cleaner for a disk drive includes a rigid material with a textured surface. An actuator in the disk drive moves the heads onto the disk surface for reading/writing information on the disk. When the heads are moving out of engagement with the disk surface they are moved to a parked position in which they come together on the head cleaner of the present invention. The actuator moves the heads a short distance on the head cleaner.
Further in accordance with the invention, the texture lines on the head cleaner are not parallel to the direction of the motion of the slider and they form a crosshatched pattern. The head cleaner cleans the head through light abrasion during the head load/unload process. Because of this it is very effective in removing debris that are smeared onto the head slider surface thus preventing head degradation.
In an alternate embodiment of the invention, the surface of the head cleaner is coated with a protective coating commonly known as DLC (Diamond Like Carbon). The DLC coating can provide better wear resistance of the head cleaner. A thin layer of lubricant can be added on the DLC coating as well.
In yet another alternative embodiment of the invention, the rigid head cleaner is placed next to a soft felt like head cleaner such that the soft head cleaner works to remove debris in secondary surfaces of the slider while the rigid head cleaner cleans the debris from the primary surfaces of the slider body.
The foregoing and further objects features and advantages of the invention will be better understood from the following more detailed description and appended claims.